兼具抗氧化及鲜度指示特性的结冷胶基活性智能膜研究

Preparation and Applications of Active and Intelligent Film Based on Gellan Gum

利用低酰基结冷胶和紫甘蓝花青素制备了兼具抗氧化活性和鲜度指示特性的活性智能膜,考察了结冷胶紫甘蓝花青素成膜溶液的流变特性,以及活性智能膜的理化性质、抗氧化活性、酸度敏感性和微观结构演化。此外,还考察了活性智能膜在大黄鱼新鲜度指示与猪油保鲜中的应用性能。结果表明,在降温过程中,成膜溶液经历了液固转变。花青素质量浓度越高,成膜溶液的储能模量和损耗模量越大,凝胶温度越高。随着花青素质量浓度的增加,活性智能膜的含水率和抗拉强度逐渐减小,厚度、水蒸气透过率和断裂伸长率则逐渐增大。花青素的加入赋予了活性智能膜良好的抗氧化活性与酸度敏感性,并可提高膜的热稳定性。活性智能膜可用于大黄鱼新鲜度指示且可有效延缓猪油的氧化酸败。

Food packaging performs three basic functions:containment,preservation of quality,and protection from environmental,physical,and microbiological factors.In recent times,the role of packaging has increased beyond its basic function with changing consumer preferences and expectations.Now,it is also contributing towards extending the shelf life and acts as a quality indicator of the packed food products.The focus is also on the development of active and intelligent packaging.An active and intelligent film with antioxidant activity and freshness indicator was prepared by using low-acyl gellan gum and red cabbage anthocyanins.The rheological behaviors of gellan gumred cabbage anthocyanin film forming solution were studied.Moreover,the effect of anthocyanin concentration on the physicochemical properties,antioxidant activity,pH color response properties and microstructure of film was measured.In addition,the application performance of film in freshness indication of large yellow croaker and lard preservation were carried out.The results of dynamic measurement showed that the film-forming solution underwent a liquid-solid transition during the cooling process.The dynamic modulus and gelation temperature of film forming solution was increased with the increase of anthocyanin concentration.With the increase of anthocyanin concentration,the moisture content and tensile strength were gradually decreased,while the thickness,water vapor permeability and elongation at break were increased gradually.The addition of anthocyanins endowed the film with good anti-oxidation and pH response properties,and it can improve the thermal stability of the film.The changes of lard quality and freshness indexes of large yellow croaker(volatile base total nitrogen content,total number of colonies and thiobarbituric acid value)and the color differenceΔE of the active intelligent film during storage were investigated.Correlation analysis showed that the color difference of the film had a significant correlation with each freshness index of large yellow croaker.The active and intelligent film can effectively delay the oxidative rancidity of lard,and it had excellent preservation performance for lard.